I bought a tire chock on eBay and began to remove rust prior to repainting. Before completing this process, I took the chock to my 280SL and, darn it, it was too high for the "arm" that fits over it. Money wasted because, having begun the repainting, I could not ask to return it. I concluded the chock had come from a larger M-B model than my W113. I then saw two more chocks on eBay, both out of W113s. I knew enough to ask the measurements, and both were too large. The seller of yet another W113 chock that was "too big" for my car suggested that the "arm" that fits over the chock may have been knocked down at some point. I doubted that, because it felt so solid, but nevertheless hit it with several up-strokes of a hammer that I placed on its side to create room to swing it. After several strokes, the arm now fits the original chock I bought on eBay! Plus, the arm is still as solid as ever. This story does not advance my Pagoda IQ, but I hope my experience helps any of you who may need a chock for your W113. BigLou